Manufacture of butyric acid



. UNITED STATES PArENT OFFICE...

FRANK ALEX. MUDERMOTT, OF WASHINGTON, DISTRICT OF COLUMBIA, AND RUTH GLASGOW, DI PITTSBURGH, PENNSYLVANIA, ASSIGNORS, BY MISNE ASSIGN- IENTS, TO THE FLEISCHMANN COMPANY, A CORPORATION OF OHIO.

MANUFACTURE OF BUTYRIC ACID.

Specification of Letters IPatent.

1'0 Drawing. Original application filed December 22, 1915, Serial No. 68,267. Divided and this application filed December 13,

To all whom it may concern.

' Be it known that we, FRANK ALEXANDER MCDERMOTT and RUTH GLAscoW,'citizens of the United States, residing, respectively, at Washington, in the District of Columbia,

' and Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in the Manufacture of Butyric Acid, of which the following is a speci cation.

This invention relates to the manufacture, or derivation, of butyric acid, and one of our objects has been the perfecting of a method by which utilization can be made of the waste liquor by-products resulting from the manufacturing operations in distilleries, breweries, yeast and vinegar factories, and places whene kindred commodities are produced, such by-p-roducts being typified by what is generally .called spent beer or That there may be a clear understanding ofthe different steps which we follow in pursuing the process which we have discovered, and of'the conditions of the various materials at successive stages in the treatment of by-products, such as are above specified, we will describe the steps we have predetermined for the manufacture of this acid from the waste fluids obtained in producing yeast and alcohol.

And as the latter products may be obtained in any of the well known ways it will not be necessary, for those skilled in the art, to describe or set forth in details the course pursued in the manufacture of the yeast, and only the important steps of the series will be referred to.

First a mash is formed containing barley or barley sprouts, corn, and the other materials usually employed, commingled with a suitable body of water. The fluid mass comprising these is subjected to the proper temperature and the other conditions necessally for saccharification.

fter saccharifying the wash is drawn off to the filtering apparatus wherein there is effected a separation of the liquid components and the materials in solution, from the solid ingredients. The fluid element after.

1917. Serial No. 206,968.

filtering and after being suitably tempered is carried to the tanks or yeast-fermentation vats. A relatively small quantity of yeast is supplied and masses ,of yeast cells. are propagated therein, with the roduction of the usual materials that are a ways collectively formed, such as alcohol, glycerol, etc; the yeast organisms appropriating from the original mass those sugar bodies and those parts of the proteins which they can utilize, and which are modified during the yeast fermentation.

, After the culture of the yeast has reached the predetermined point the. total mass from the yeast vats is withdrawn and subjected to treatment for separating the yeasty mass from the liquor, this being commonly accomplished in centrifugal machines. The solid yeast components are conducted away from the separating mechanism in one direction for final preparation, and the fluid ingredients that come from the'yeast vats are taken totanks or collectors.

This fluid mass taken from the separators comprises as its components, water, alcohol, fusel oil, aldehydes, etc. Thisfluid, is

subjected to distillation for driving ofl and I pentosans, etc.) proteins, simpler nitrogeneous substances, mineral salts, and lactic and succinic acids.

The relative quantities of the materials last specified will of course'vary from time to time, as the materials initially used on one occasion vary more or less from those used on another, and as the conditions for each stage of the yeast manufacture in one series of steps (constituting one complete operation) difler from the conditions which characterize the corresponding stage in another operation.

But the following can be taken as an approximate statement of the percentages the present subject matter, namely,

. thereabouts.

Water 99. 000 Glycerol Proteins and mtrogenous substances N onfermentable sugars (pentoses,

0 I I 0 I Lactic acid and traces of succimc acid Mineral salts .lllO

This fluid mass (just described as that leavingithe distilling apparatus) is taken off at relatively high temperature, 98 C. or

nd to attain' our purposes we maintain a high temperature (90 C. and upward) during the early stages .of that treatment which we have evolved and to which we subject it after the alcohol has been distilled. We have discovered that when there are proper conditions of temperature, and closely regulated conditions of acidity and alkalinity a slop or spent beer of this character. can be utilized for the production of butyric acid by developing and propagating therein micro-organisms of either of a number of genera, such as Gramlobacter smcaharobutyrimtm, Bacillus wbtz'Z/is, or Bawillmboocopricus.

None of these organisms will propagate or thrive in a medium which is .not accurately and delicately regulated as to its acidity and temperature. If it be highly acidified, as for instance by the lactic acid which results in the manufacture of yeast, they will not thrive. We therefore, while the mass isstill relativel highly heated (for example at 90 C. or t ereabouts) neutralize the greater art .of the acid component by a suitable asic reagent. For this properly prepared anhydrous ,lime can be used economically and with ood results. The acidity is, by

this, broug t down close to the line of neutralization. In most cases we prefer to allow a slight amount of acid to remain. Howver, we add to the liquor, while still hot,- as aforesaid, a slight excess of a suitable carbonate (such as calcium carbonate) which remains inert until a later stage in the process, and, therefore, at this stage, leaves the mass, as stated, slightly acid. Or, this carbonate may be added in portions during the course of fermentation.

When properly prepared the fluid mass is now ready for introducing a micro-organism of the proper genus.

, he organisims for this purpose may be provided from specially formed artificial cultures; but when 0 erating on a large scale we prefer to deve op them from mate for the top cheaply. For example malt sprouts can be used for inoculating the liquid. If. subtilis is to be utilized 'it can be developed and propagated abundantly from any of the ordinary varieties of hay.

.The organisms which we develop (say of the Granulobacter genus) are spore formers. We introduce them to the fluidmass, when it is at a high temperature, or bring them to such high heat at an early time after introducing them, and at such heat all of the organisms of the other varieties, such as the non-spore formers, are destroyed. The spores from the organisms of the variety which we desire to utilize survive, however. After a short period we lower the temperature to the polnt where they will germlnate and a culture of the organisms can form. These becomeactive, deriving nourishment from. the ycerol and from the calcium lactate which has been formed by the neutralizing of the lactic acid with lime, and they also I appropriate a considerable portion of the protein and of the non-yeast-fermentable sugars. The micro-organisms utilize these ingredients to supply materials for both cell building and energy, and during the activities in this connection produce butyric acid in addition to other products.

Durin this stage of butyric fermentation air shou d beexcluded from the mass; at least air should not be admitted largely to contact with it. This'can be accomplished, under ordinary circumstances, by a cover of the vessel holding the mass suitably to exclude the atmosphere.

At the end of the stage of fermentation the .ingredients of the fluid mass, as an entirety, can be consideredas (a) water, (6) calcium butyrate, (a) some free acid, mainly butyric, (d) mineral salts, (e) such residual proteins and other nitrogenous bodies and (f) non-yeast-fermentable sugars as have escaped the action of the or anisms, (g) the decomposition products t at have been is present in relatively large quantities.

From the fluid mass thus obtained the, butyric acid is separated. This can be accomplished by (a) concentrating (if necessary) the initial mass; (6) then adding a precipitant (such as copper chloride for example) suitable for forming an insoluble, or approximately insoluble precipitate; (c) the filtering, or otherwise mechanically separatv ing, the compound from the liquor mass;

(d) decomposing this compound, as by addin m ss the butyric acid freed by the decomposition; and collecting the distillate.

In racticing the process thus indicated the initial liquor obtained from the butyric fermentation is rendered relatively alkaline by adding an active body, or an inactive one,

or both, as found necessary, in sufficient quantity; following in this respectthe procedure set forth above. Then the mass is concentrated as precipitation is more effective in a concentrated fluid.

At this stage the mass can, as above'described, be regarded as comprising the following components: water, calcium butyrate, proteins, protein decomposition products}, sugar, bacterial cells, and some free aci v The concentrate is now rendered sufficiently acid (by adding a mineral acid in suflicient amount) to decompose the calcium butyrate which is present.

We then add an excess of a reagent, such as ferrous sulphate, to precipitate the proteins, the protein decomposition products, and the bacterial cells, etc.

This reagent, however, should be neutral 7 as to butyric acid so as not to form a precipitate therewith.

After this first precipitant has finished its work the liquid mass is subjected to filtration to separate the liquid from the first precipitate.

To the liquid filtrate we then add. cupric chloride in solid form, the mass being preferably stirred at this time, and cupric buty rate is-formed. It is but slightly soluble in water, and after the reaction is completed the liquor is again filtered and the liquid is separated from the precipitate.

A strong acid is then added tothe precipitate capable of decomposing the butyrate and forming salt with the copper, the butyric acid being freed by a ,strong acid, meaning one having normally a greater combining strength than butyric acid.

From the resulting mass the butyric acid is then distilled, use being made of a suitable 50 retort, either by external heating or by means of a current of steam. The collecting and condensing devices may be of any suitable character.

The adding of the ferrous sulphate or equivalent prior to introducing the copper chloride is advantageous as it results in the removal of the proteins before they can act upon the chloride, and the latter body is reserved entirely for acting on the butyric acid. Copper chloride is. also a reagent relative to the organic materials of the protein class,

a suitable acid; (6) distilling from the understood, we do and much of it would be used up' in precipicedure conforming to the method which We have devised.

And, again, while we have above described, somewhat in detail, specific materials or bodies, and proportions, in order that, as stated, the process may be readily not limit ourselves thereto.

What weclaim is:

1. The herein described method for separating butyric acid from a fluid mass which consists in introducing an alkali, forming a butyrate salt which is insoluble in water, then separating the said salt from the liquid mass, then adding an acid stronger than butyric acid to decompose the salt and free thedbutyric acid, and then distilling off the am 2; The herein described method for sepa rating butyric acid from a fluid mass containing it, consisting in adding cupric chloride to the mass and causing the butyric acid to form coppr butyrate,-then separating such butyrate from the mass, then decomposing the butyrate by an acid stronger than butyric acid and freeing the latter, and then separating it from the mass.

3. The herein described method for separating butyric acid from a fluid mass containing the acid or containing a butyrate, together with organic matters, which consists in introducing a precipitant adapted to render the organic materials insoluble in Water, then separating the fluid mass from the precipitated materials, then forming an insoluble butyrate salt, and then decomposing the salt and separating therefrom the butyric acid.

4:2 The hereindescribed method for separating butyric acid from a fluid mass containing a butyrate salt and organic. matter, which consists in acidifying the mass and decomposing the butyrate salt, introducing ferrous sulphate and precipitating the organic matter, then separating the liquor from the precipitated materials, forming an insoluble butyrate salt, and then decomposing the butyrate and separating the butyric acid.

In testimony whereof, we hereunto set our hands this 9th da of October, 1917.

- F XLEX. ,MoDER-MOTT.

RUTH GLASGOW. 

